Affinity products are designed to be used in conjunction with multitouch devices (Magic Mouse and trackpads), including those with Force Touch pressure-sensitive capability (Magic Trackpad 2 and built into recent MacBooks).
The following gestures are available in your Affinity app when using a trackpad:
Disabling a multitouch gesture is system-wide, not just for your Affinity app.
Disabling this feature is system-wide, not just for your Affinity app.
Force Touch can be used as an alternative to -clicking or using macOS's Secondary click trackpad gesture (if enabled).